Image recording/reproducing apparatus

ABSTRACT

A video recording/reproducing apparatus capable of discriminating commercial message portions even when a broadcasting mode is the same. A magnetic head records television broadcasting signals to a magnetic tape and reproduces the television broadcasting signals from this magnetic tape. When the television broadcasting signals are reduced by recording/reproducing apparatus, an audio-free portion detector detects audio-free portions from audio signals in the television broadcasting signals. Commercial message (CM) portion detector detects the commercial message portions in the television broadcasting signals by the time intervals among a plurality of audio-free portions detected by the audio-free portion detector, and a CM information memory circuit stores the information of the recording positions of the commercial message portions detected by this commercial message portion detector to the magnetic tape. When the television broadcasting signals are reproduced from the magnetic tape, reproduction is carried out while the commercial message portions are skipped, at the recording positions of the commercial message portions to the magnetic tape, on the basis of the information of the recording positions of the commercial message portions to the magnetic tape that are stored in the memory circuit.

This application is a continuation of application Ser. No. 08/949,335,filed Oct. 14, 1997, U.S. Pat. No. 6,002,831, which is a continuation ofSer. No. 08/648,815, filed May 16, 1996 abandoned.

BACKGROUND OF THE INVENTION

This invention relates to a video recording/reproducing apparatus andmore specifically, to a video recording/reproducing apparatus forrecording and reproducing television broadcasting signals anddistinguishing commercial message portions and program content portionsin a broadcasting program.

A video recording/reproducing apparatus is known which distinguishescommercial message portions from program content portions fromtelevision broadcasting signals when the television broadcasting signalsare recorded, and records the program content portions by omitting thecommercial message portions. Video recording/reproducing apparatuses ofthis kind include a bilingual broadcasting mode judgement systemdescribed in JP-A-3-158086 and a stereophonic broadcasting modejudgement system described in JP-A-3-262287, for example.

Since the commercial messages are broadcasted by the stereophonicbroadcasting in the system described in JP-A-3-158086, this systemjudges the bilingual broadcasting mode contained in audio signals oftelevision broadcasting, distinguishes the program content portions ofthe bilingual broadcasting mode from the commercial message portions ofthe stereophonic broadcasting mode, automatically omits only thecommercial message (CM) portions and records the program contentportions of the bilingual broadcasting mode.

On the other hand, the system described in JP-A-3-262287 judges thestereophonic broadcasting mode contained in the audio signals oftelevision broadcasting, distinguishes the program content portions ofthe stereophonic broadcasting mode from the commercial message portionsof the monaural broadcasting mode, automatically omits only thecommercial message portions and records the program content portions ofthe stereophonic broadcasting mode.

In the systems according to the prior art described above, however,automatic omission of the CM portions cannot be effected in thebilingual broadcasting mode judgement system when the program contentportions are the monaural broadcasting program and the stereophonicbroadcasting program. In the stereophonic broadcasting mode judgementsystem, the CM is originally based on the assumption that it isbroadcasted by monaural broadcasting. Therefore, if the CM itself isbroadcasted by stereophonic broadcasting, it cannot be distinguishedfrom the stereophonic broadcasting programs.

Therefore, the conventional systems intend to distinguish two kinds ofprogram contents from the difference of the broadcasting modes ofbilingual broadcasting, monaural broadcasting and stereophonicbroadcasting. For this reason, when the program content portions and thecommercial message portions have the same broadcasting mode, they cannotbe distinguished from one another.

Particularly recently, bilingual broadcasting and stereophonicbroadcasting have been employed for the program content portions, too,not only for picture programs but also for ordinary programs such asmusic programs, sports programs, drama programs, and so forth.Therefore, the possibility drops that the prior art system can omit onlythe commercial message portions, and these systems have become of nopractical use.

SUMMARY OF THE INVENTION

It is therefore an object of the present invention to provide a videorecording/reproducing apparatus which can distinguish commercial messageportions even in the same broadcasting mode.

In a video recording/reproducing apparatus includingrecording/reproducing means for recording television broadcastingsignals to a recording medium and reproducing the broadcasting signalsfrom the recording medium, the object of the present invention describedabove can be accomplished by a video recording/reproducing apparatuswhich comprises audio-free portion detection means for detectingaudio-free portions from audio signals in television broadcastingsignals when the television broadcasting signals are recorded by therecording/reproducing means, commercial message portion detection meansfor detecting commercial message portions in the television broadcastingsignals by the time intervals among a plurality of the audio-freeportions detected by the audio-free portion detection means, memorymeans for storing information of recording positions of the commercialmessage portions detected by the commercial message portion detectionmeans to the recording medium, and control means for controllingreproduction from the recording medium at the time of reproduction ofthe television broadcasting signals from the recording medium by therecording/reproducing means, on the basis of the information of therecording positions of the commercial message portions stored in thememory means to the recording medium, so that reproduction can becarried out while the commercial message portions are skipped, at therecording positions of the commercial message portions to the recordingmedium.

Preferably, the video recording/reproducing apparatus described abovefurther comprises video signal detection means for detecting changingpoints of video signals from the video signals in the televisionbroadcasting signals at the time of recording of the televisionbroadcasting signals by the recording/reproducing means, wherein thecommercial message portion detection means detects the commercialmessage portions in the television broadcasting signals on the basis ofthe time intervals among a plurality of audio-free portions and the timeintervals of the changing points of a plurality of video signalsdetected by the audio-free portion detection means and the video signaldetection means, respectively.

In the video recording/reproducing apparatus described above, thecommercial message portion detection means preferably detects the pointat which the video signal level changes to a black level as the changingpoint of the video signal.

In the video recording/reproducing apparatus described above, thecommercial message portion detection means preferably detects the pointat which the video signal level changes to a white level as the changingpoint of the video signal.

In the video recording/reproducing apparatus described above, thecommercial message portion detection means preferably detects the pointat which the video signal level greatly changes as the changing point ofthe video signal.

In the video recording/reproducing apparatus described above, the memorymeans preferably comprises a semiconductor memory.

In the video recording/reproducing apparatus described above, the memorymeans preferably comprises the recording medium to which the televisionbroadcasting signals are recorded by the recording/reproducing means.

In the video recording/reproducing apparatus described above, theinformation of the recording position of the commercial message portion,which is stored in the recording medium by the memory means, ispreferably stored at the leading position of the recording medium.

In the video recording/reproducing apparatus described above, theinformation of the recording position of the commercial message portionstored to the recording medium by the memory means to the recordingmedium is preferably stored at the leading positions of a plurality oftelevision signals to be recorded to the recording medium, respectively.

In the video recording/reproducing apparatus described above, theinformation of the recording position of the commercial message portionstored to the recording medium by the memory means is preferably storedat the leading position and the end position of the commercial messageportion contained in each of a plurality of television signals recordedto the recording medium.

In the video recording/reproducing apparatus described above, theapparatus further comprises mode judgement means for detecting thecommercial message portions in the television broadcasting signals atthe time of recording of the television broadcasting signals by therecording/reproducing means, on the basis of the difference ofbroadcasting modes between program content portions of the televisionbroadcasting signals and the commercial message portions, and whereinthe commercial message portion detection means detects the commercialmessage portions in the television broadcasting signals on the basis ofthe time intervals among a plurality of audio-free portions, the timeintervals of the changing points of a plurality of video signals and thedifference of the broadcasting modes detected by the audio-free portiondetection means, by the video signal detection means and by the modejudgement means, respectively.

In the video recording/reproducing apparatus described above, thecommercial message portion detection means detects recorded portions asthe commercial message portions when the time intervals so detected aresubstantially some multiples of N seconds.

In the video recording/reproducing apparatus described above, thecommercial message portion detection means judges the recorded portionsas the commercial message portions when at least two time intervalshaving substantially some multiples of N seconds are detectedconsecutively.

The video recording/reproducing apparatus of the present inventionincludes the audio-free portion detection means for detecting audio-freeportions from audio signals of the television broadcasting signals atthe time of recording of the television broadcasting signals by therecording/reproduction means, the commercial message portion detectionmeans for detecting commercial message portions in the televisionbroadcasting signals by the time intervals among a plurality of theaudio-free portions detected by the audio-free portion detection means,the memory means for storing information of recording positions of thecommercial message portions detected by the commercial message portiondetection means to the recording medium, and control means forcontrolling reproduction from the recording medium at the time ofreproduction of the television broadcasting signals from the recordingmedium by the recording/reproducing means, on the basis of theinformation of the recording positions of the commercial messageportions stored in the memory means to the recording medium, so thatreproduction can be carried out while the commercial message portionsare skipped, at the recording positions of the commercial messageportions to the recording medium. Since the commercial message portionscan be reproduced skippingly by using the time intervals of theaudio-free portions of the audio signals in the television signals, thecommercial message portions can be discriminated and can be reproducedeven when the broadcasting mode is the same.

Since the apparatus of the present invention further includes the videosignal detection means for detecting the changing points of videosignals from the video signals in the television broadcasting signals atthe time of recording of the television broadcasting signals by therecording/reproducing means, the commercial message portion detectionmeans detects the commercial message portions in the televisionbroadcasting signals on the basis of the time intervals of a pluralityof audio-free portions and the time intervals of the changing points ofa plurality of video signals detected by the audio-free portiondetection means and the video signal detection means, respectively.Therefore, the commercial message portions can be distinguished morecorrectly.

Further, the commercial message portion detection means can easilydistinguish the changing point because it detects the point at which thevideo signal level changes to a black level as the changing point of thevideo signal.

The commercial message portion detection means can easily distinguishthe changing point in the same way as the black level because it detectsthe point at which the video signal level changes to a white level asthe changing point of the video signal.

The commercial message portion detection means can distinguish thechanging points, inclusive of the fade-out portions, because it detectsthe point at which the video signal level greatly changes as thechanging point of the video signal.

When the memory means comprises a semiconductor memory, storage can bemade at the time of recording.

When the memory means comprises the recording medium to which thetelevision broadcasting signals are recorded by therecording/reproducing means, existing recording media can be utilizedand new memory means need not be used.

When the information of the recording position of the commercial messageportion to be stored in the recording medium by the memory medium isstored at the leading position of the recording medium, all theinformation can be written once again at the time of overwrite.

Further, when the information of the recording position of thecommercial message portion to be stored in the recording medium by thememory means to the recording medium is stored at the leading positionof each of a plurality of commercial message portions stored in therecording medium by the memory means, the rewinding quantity of therecording medium after completion of recording can be reduced.

The information of the commercial message portion stored in therecording medium by the memory means to the recording medium is storedat the leading position and the end position of the commercial messageportion contained in each of a plurality of television signals stored inthe recording medium. Therefore, skip reproduction can be carried out assuch from the present position at the time of reproduction.

Because the apparatus of the present invention further includes the modejudgement means for detecting the commercial message portions in thetelevision broadcasting signals at the time of recording of thetelevision broadcasting signals by the recording/reproducing means, onthe basis of the difference of broadcasting modes between the programcontent portions of the television broadcasting signals and thecommercial message portions, the commercial message portion detectionmeans detects the commercial message portions in the televisionbroadcasting signals on the basis of the time intervals of a pluralityof time intervals, the time intervals of the changing points of aplurality of video signals and the difference of the broadcasting modesdetected by the audio-free portion detection means, the video signaldetection means and the mode judgement means, respectively. Therefore,the commercial message portions can be distinguished more correctly.

The commercial message portion detection means judges recorded portionsas the commercial message portions when the time interval so detected issubstantially some multiples of N seconds, and can therefore distinguisheasily the commercial message portions.

The commercial message portion detection means judges recorded portionsas the commercial message portions when at least two time intervalshaving substantially some multiples of N seconds are detectedconsecutively, and can therefore distinguish correctly the commercialmessage portions.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a block diagram of a video recording/reproducing apparatusaccording to one embodiment of the present invention;

FIG. 2 is an explanatory view useful for explaining a CM judgementmethod according to one embodiment of the present invention;

FIG. 3 is a block diagram of a video recording/reproducing apparatusaccording to another embodiment of the present invention;

FIG. 4 is a block diagram of a video recording/reproducing apparatusaccording to still another embodiment of the present invention;

FIG. 5 is a schematic view of a magnetic tape in a transverse directionaccording to still another embodiment of the present invention;

FIG. 6 is a schematic view of a magnetic tape in a transverse directionaccording to still another embodiment of the present invention;

FIG. 7 is a schematic view of a magnetic tape in a transverse directionaccording to still another embodiment of the present invention; and

FIG. 8 is a block diagram of a video recording/reproducing apparatusaccording to still another embodiment of the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

A first embodiment of the present invention will be explained withreference to FIG. 1.

FIG. 1 is a block diagram of a video recording/reproducing apparatusaccording to the first embodiment of the present invention.

A magnetic tape 1 is normally fed at a constant speed, and this speed iscontrolled by a capstan 2 so disposed as to oppose a pinch roller 3while clamping the magnetic tape 1 between them.

Two magnetic heads 4 are fitted to a rotary cylinder 5 with an angulargap of 180° between them. The magnetic tape 1 is wound on this rotarycylinder 5, and television broadcasting signals are recorded orreproduced by the magnetic heads 4. These two magnetic heads 4 areswitched by a magnetic head changeover switch 6 and are selectivelyused, so that reproduction signals which are continuous time-wise can beobtained. Here, the magnetic head changeover switch 6 switches eitherone of the heads 4 which is in contact with the magnetic tape 1 so thatthe selected head 4 can select the reproduction signals of the tape withwhich it keeps contact. The timing of this switching operation isgenerally acquired by detecting the magnetic field generated by a magnet(not shown) fitted to the rotary cylinder 5 by means of a sensor (notshown).

A magnetic tape drive motor 8 is used so as to drive the capstan 2 andto drive a take-up reel for taking up the magnetic tape 1, and thenumber of revolution of this motor 8 is controlled in accordance withthe modes of operation such as a normal speed mode, a fast-forward mode,etc.

Control pulses used for a variety of controls are recorded on themagnetic tape 1 in addition to the ordinary television broadcastingsignals, and this recording operation is carried out by using astationary head 7 for the control pulses. The control pulses arerecorded in a {fraction (1/30)} second interval.

The explanation will be hereby given on the case where the televisionbroadcasting signals in which CM (Commercial Message) exists arerecorded.

The television broadcasting signals are inputted to an antenna 21 andare supplied to a tuner 20. A desired program is selected by the tuner20. The program selected by the tuner 20 is subjected to conversionprocessing in an audio signal processing circuit 10 and is outputted asRF (Radio Frequency) audio signals. These RF audio signals arealternately sent to the two magnetic heads 4 and are recorded on themagnetic tape 1. The TV broadcasting signals are also subjected toconversion processing in a video signal processing circuit 17, areoutputted as video signals of a base band, are sent alternately to thetwo magnetic heads 4 through the magnetic head changeover switch 6, andare recorded on the magnetic tape 1.

When recording is started, a tape position information read/writecircuit 14 simultaneously records an identification number of the tapewith a time code representing the position information of the tape, etc,on the magnetic tape 1 through the magnetic head 4. This information isencoded and written into a V blanking portion, or the like, of the videosignal, for example. The identification number of the tape is the numberthat compulsively applies 99 titles to each magnetic tape in accordancewith the command from the microcomputer 13.

On the other hand, the signal outputted as the audio signal in the audiosignal processing circuit 10 is supplied to an audio signal leveldetector 9. This audio signal level detector 9 detects the level of theaudio signal. The audio signal level detector 9 comprises a smoothingcircuit, for example, smoothes a low frequency audio signal and picks upa D.C. signal.

The magnitude of the level detected by the audio signal level detector 9is supplied to an audio signal no level detector 11. The audio signal nolevel detector 11 detects the point at which the audio signal level isclose to zero, and the signal so detected is supplied to themicrocomputer 13. The audio signal no level detector 11 comprises acomparison circuit, for example, and its reference voltage is set to 0 Vor a voltage slightly greater than 0 V. The level of the inputted audiosignal is compared with this reference voltage, and a level “1” isoutputted when the level of the audio signal is higher than thereference voltage. Here, the level “1” can be outputted, too, byincorporating a NOT circuit in this circuit when the level of the audiosignal is lower than the reference voltage.

The output of the audio signal no level detector 11 is applied to themicrocomputer 13. The microcomputer 13 stores the time of the detectionsignal supplied this time from the audio signal no level detector 11 andrepresenting the audio signal no level portion as well as the positioninformation of the tape supplied from the tape position informationread/write circuit 14, measures the time interval between both detectionsignals when the detection signal of the next time representing theaudio signal no level portion is detected, and judges the information asCM (commercial message) when the interval between the detection signalof this time and the detection signal of the next time has apredetermined time interval. The position information of the tape is theinformation of the time codes corresponding to the absolute address(absolute time) from the leading position of the tape and to anX-minute/Y-second Z-frame. The method of judging the information as theCM will be explained later with reference to FIG. 2.

Incidentally, in the foregoing explanation, the audio signal no leveldetector 11 is a discrete circuit from the microcomputer 13. However,because the latest microcomputers 13 have a built-in A/D convertorhaving a plurality of channels, the audio signal no level portion may bedetected by directly applying the signal of the audio signal leveldetector 9 to the microcomputer 13 to effect A/D conversion and thencomparing it with the reference voltage inside the microcomputer 13.

On the other hand, the signal outputted as the video signal of the baseband in the video signal processing circuit 17 is supplied to the videosignal level detector 16. This video signal level detector 16 averagesthe points at which the video signal level fades out and changes to theblack level or to the white level and the signal levels of the screen,and detects the change points such as the point at which the signallevel drastically changes (switching point of scenes, etc.). The videosignal level detector 16 comprises a frame integration circuit, forexample. The frame integration circuit is triggered on the basis of avertical sync signal (V-sync) in the video signal and integrates thevideo signals of one frame. In consequence, the mean level of the videosignals of the one frame is determined, and the magnitude of the levelof the video signal is detected. The magnitude of the level of the videosignal detected by the video signal level detector 16 is supplied to thevideo signal detector 18.

The video signal detector 18 compares the mean level obtained in thisway with the reference voltage of the comparison circuit. Here, when thesignal subjected to frame integration is higher than the referencevoltage by setting the reference voltage to a voltage slightly higherthan the black level, the comparison circuit judges the level as theblack level and outputs it. It is of course possible to use a NOTcircuit and to output the black level from the comparison circuit whenthe frame-integrated signal is lower than the reference voltage.

When the reference voltage is set to a voltage slightly lower than thewhite level, the comparison circuit judges the level as the white leveland outputs it when the frame-integrated signal is higher than thereference voltage.

The points at which the signal level drastically changes (switchingpoint of scenes) can be detected by constituting the video signaldetector 18 by a differential circuit and a comparison circuit so thatthe differential circuit differentiates the signal level and thecomparison circuit detects whether or not the differential value isgreater than the reference value.

It is customary in the United States to employ fade-out before and afterthe commercial message portion and it is customary in Japan to switchthe scene. However, there is the case where fade-out is employed inJapan, too, and in such a case, too, a system is employed which detectsthe point at which the signal level drastically changes (switching pointof the scene). For, when fade-out occurs, the level of the signalchanges before and after this fade-out, and judgement can be made in thesame way as in switching of the scene.

In the explanation given above, the video signals of one frame areintegrated, but this one frame is not particularly necessary. In short,the change point of the scene needs be detected. Therefore, only thesignals in the proximity of the center of the screen may be integrated.To integrate the video signals corresponding to the horizontal scanninglines of the 100th to 150th lines, for example, the integration circuitis triggered in such a manner as to start operating after the passage ofa predetermined signal from the vertical sync signal (V-sync) on thebasis of this signal, and the integration operation is conductedthereafter for a predetermined time.

Though the comparison circuit is a separate circuit from themicrocomputer 13 in the foregoing explanation, it is also possible todirectly apply the signal of the integration circuit to themicrocomputer 13 so as to conduct A/D conversion because the latestmicrocomputers 13 have a built-in A/D convertor having a plurality ofchannels, and the change point of the video signal is thereafterdetected by comparing the signal with the reference voltage or comparingthe mean level between the frames inside the microcomputer 13.

The video signal detector 18 supplies the detection signal to themicrocomputer 13. The microcomputer 13 measures the time interval of thedetection signals from the time of the detection signal of this timesupplied from the video signal detector 18 and the time of the detectionsignal of the next time, and judges the signal as the CM when the timeinterval between the detection signal of this time and the detectionsignal of he next time is a predetermined interval. The method ofjudging the CM will be explained later with reference to FIG. 2. Whenthe detection signals by the audio signal and the video signal areoutputted, the tape position information supplied from the tape positioninformation read/write circuit 14 is simultaneously stored in themicrocomputer 13.

The signals are judged as the CM by using both of the judgement of theaudio signal no level portion from the features of the audio signal andthe video signal and the judgement of the changing portion or thefade-out portion of the video signal, and the position information ofthe start of the CM and its end and the tape recognition number aresupplied to the CM information memory circuit 12. The CM informationmemory circuit 12 stores the tape recognition number and the tapeposition information as the CM information. The CM information memorycircuit 12 for storing this CM information may comprise a semiconductormemory such as an EEPROM or an RAM, or a magnetic tape. In other words,the position information of the CM is sequentially stored in the CMinformation memory circuit 12 during the recording mode while theprogram is being recorded.

Incidentally, while the judgement of the CM is carried out in the waydescribed above, the audio signal and the video signal are recorded tothe magnetic tape 1 through the magnetic head 4 in the same way as inordinary video signal recording apparatuses. In this instance, all theprogram content portion and the commercial message portion are recordedunlike the prior art in which recording is made while the CM portion isomitted. In the reproduction mode, reproduction is effected while thecommercial message portion is skipped.

Next, reproduction of the recorded program will be explained.

During the reproduction mode, the tape position information and the taperecognition number written to the magnetic tape are read out by the tapeposition information read/write circuit 14. The tape positioninformation and the tape recognition number so read out are supplied tothe microcomputer 13. The microcomputer 13 looks up the CM positioninformation of the tape during reproduction, which is stored in the CMinformation memory circuit 12, on the basis of the tape recognitionnumber.

The microcomputer 13 distinguishes the CM portion from the programportion from the tape position information during reproduction on thebasis of the CM position information looked up from the CM informationmemory circuit 12, and sends a fast-forward command or a fast-playcommand to the tape driving circuit 15 so as to skip the CM portion whenthe CM portion of the tape is reached.

In the fast-forward mode, it is not possible to reproduce the videosignals and the audio signals from the magnetic tape 1 and it is notclear, either, from the screen of the television receiver whether theoriginal commercial message portion is skipped or the program contentportion is skipped. In fast-play, on the other hand, the video isdisplayed on the screen to a certain extent, though the video isreproduced at a high reproduction speed. Therefore, the user canidentify whether the commercial message portion is skipped or theprogram content portion is skipped. For this reason, fast-play ispreferably employed for such a need.

The tape driving circuit 15 drives the motor 8 in accordance with thecommand given thereto, and causes the magnetic tape 1 to travel at ahigh speed. The microcomputer 13 calculates the number of control pulsesexisting from the start position of the CM to its end position from theCM information, and also counts the number of control pulses suppliedfrom the control pulse read/write circuit 22 from the CM start position.When the number of the control pulses so counted reaches the number ofthe control pulses existing in the CM portion, the microcomputer 13sends the command to the tape driving circuit 15 to stop thefast-forward or fast-play operation and to return to the normalreproduction. The tape driving circuit 15 drives the motor 8 so as tolet the magnetic tape 1 travel at the standard reproduction speed. Theposition information cannot be read from the magnetic tape 1 during thehigh speed travel. Therefore, the moving distance of the tape (the timeof the CM portion) is measured by using the control pulses.

The subsequent CM portions, too, are skipped in the same way. The CMportion and the program portion are distinguished from each other by themethod described above, and only the CM is skipped. A CM skip on/offswitch 23 determines whether or not the CM skip is made on the basis ofthe user's judgement. When this switch is on, the ON signal is suppliedto the microcomputer 13, and the microcomputer 13 sends the command tothe tape driving circuit 15 so as to execute the CM skip describedabove. When this switch 23 is off, the OFF signal is supplied to themicrocomputer 13, and the microcomputer 13 does not execute the CM skip.Therefore, the commercial message portion, too, is reproduced in thesame way as the program content portion.

A broadcasting mode judgement device 24 is the CM judgement means by thebroadcasting mode judgement that has been described with reference tothe prior art technologies. This judgement device 24 discriminates thecommercial message portion from other bilingual broadcasting programsand monaural broadcasting programs provided that the commercial messageportion is broadcasted by stereophonic broadcasting. This broadcastingmode judgement device 24 only judges the commercial message portion, andrecording is not omitted on the basis of the signal of this broadcastingmode judgement device 24. The CM judgement can be made with a higherlevel of accuracy by judging the signal of the broadcasting modejudgement device 24 by the audio signal no level detector 11 incombination with the video signal detector 18.

Next, the CM judgement method will be explained with reference to FIG.2.

In FIG. 2, a thick solid line of “recording signal” represents the timeaxis. The audio signal no level detector 11 detects the portion(audio-free portion) at which the sound level becomes zero at the timerepresented by a downward arrow put on this recording signal, and it isinputted to the microcomputer 13. In this diagram, the audio-freeportion is detected at the timings t₁, t₂, t₃, t₄, t₅, t₆, t₇, t₈, t₉,t₁₀ and t₁₁, and the microcomputer 13 measures the time intervalsbetween them.

The CM is prepared and inserted in a predetermined interval (15 secondsor some multiples of 15 seconds such as 15 sec, 30 sec and 60 sec) andthe audio-free portions exist before and after the CM. The intervalbetween the audio-free portions is judged as the CM portion by utilizingthe nature of the CM described above. Quite naturally, the audio-freeportions exist in the program portion, too, but the interval betweenthem is not constant unless specifically intended. Therefore, when theinterval between the audio-free portions is greater or smaller than apredetermined interval, such portions are judged as the program. Theaudio-free portions are measured inside the microcomputer 13 while theprogram is recorded to the magnetic tape 1, and are sequentially storedand marked from the microcomputer 13 into the CM information memorycircuit 12. Furthermore, after recording is completed, the intervalportions are again edited so as to distinguish the program portions fromthe CM portions, and are then stored in the CM information memorycircuit 12.

Correctly speaking, the time interval of the audio-free portion is not15 seconds. For, the time of the audio-free portion itself is generallygreater than 50 ms. Though this time is different from the CM to the CM,it is at least 200 ms at the shortest. When the time interval of theaudio-free portion is between 14.5 seconds to 15.0 seconds, between 29.5second and 30.0 seconds and between 59.5 seconds and 60.0 seconds, suchaudio-free portions are judged as the CM portion. When this timeinterval is expanded, judgement of the CM portion can be made even whenthe time interval of the CM portion is small but in such a case, theredevelops the possibility that the original program content portion iserroneously judged as the CM portion.

Here, measurement of the time intervals by the microcomputer 13 iseffected in the following way, for example:

(t₂−t₁)=50 sec, (t₃−t₁)=65 sec, (t₃−t₂)=15 sec, (t₄−t₂)=30 sec,(t₄−t₃)=15 sec, (t₅−t₂)=45 sec, (t₅−t₃)=30 sec, (t₅−t₄)=15 sec,(t₆−t₂)=115 sec, (t₆−t₃)=100 sec, (t₆−t₄)=85 sec, (t₆−t₅)=70 sec,(t₇−t₆)=15 sec, (t₈−t₆)=30 sec, (t₈−t₇)=15 sec, (t₉−t₆)=38 sec,(t₉−t₇)=23 sec, (t₉−t₈)=8 sec, (t₁₀−t₆)=53 sec, (t₁₀−t₇)=38 sec,(t₁₀−t₈)=23 sec, (t₁₀−t₉)=15 sec, (t₁₁−t₆)=64 sec, (t₁₁−t₇)=49 sec,(t₁₁−t₈)=34 sec, (t₁₁−t₉)=26 sec, (t₁₁−t₁₀)=11 sec.

In other words, not only the time interval between the adjacentaudio-free portions but also the time interval between a givenaudio-free portion and the second next audio-free portion are measured.For, because the audio-free portions are sometimes contained in thecommercial message portion having a time length of 15 seconds or itsmultiples, the commercial message portion cannot be judged by the timeinterval of only the adjacent audio-free portions. Therefore, the timeintervals between the time t₁ and the time t₂ and between the time t₁and the time t₃ are measured for the audio-free portion at the time t₁.When the time interval between a given audio-free portion and anotherexceeds 60 seconds, on the other hand, measurement of the timedifference exceeding this time interval becomes meaningless because thecommercial message portion exceeding 60 seconds does not exist.Therefore, the subsequent measurement of the time interval is noteffected. In other words, when the time difference between the time t₁and the time t₃ is measured for the audio-free portion at the time t₁,the measurement of the subsequent time difference is no longer made.

In FIG. 2, downward arrows put on the audio-free portion represent thevideo signal changing portions. In other words, the time intervalbetween the points at which the signal level obtained by averaging thesignal levels on the screen drastically changes (the switching points ofthe scenes) is measured in the same way as the measurement of the timeintervals in the audio-free portions. As is obvious from FIG. 2, thetime interval of the image signal changing portions is shorter than thetime interval of the audio-free portion. The video signal changingportion is measured inside the microcomputer 13 while the program isrecorded on the magnetic tape 1, and the interval portions are againedited either sequentially or after recording is completed so as todistinguish the program portions from the CM portions. The microcomputer13 can correctly judge the commercial message portion by calculating theAND condition between the audio-free portion and the video signalchanging portion.

The points at which the composite signal, the luminance signal, etc,fade out and change to the black level or the white level can be used asthe changing points of the video signal, and the arrows put on the videosignal changing portion in FIG. 2 represent the fade-out portions.

In the broadcasting signals in Japan, the audio-free portions aregenerally provided before and behind the commercial message portion butin the broadcasting signals in the United States, the fade-out portionsare generally provided before and behind the commercial message portion.Therefore, it is more effective to use the method which utilizes thefade-out portions for the recording apparatuses used in the UnitedStates.

Further, the audio-free portion appearing between the time t₉ and thetime t₁₀ has the time interval of 15 seconds and cannot be judged byusing the audio signal no level detector 11 and the video signaldetector 18 described already. However, a commercial message portionhaving the time of 15 seconds seldom appears alone but two or fourcommercial message portions consecutively appear. Therefore, when theaudio-free portion having the time length of 15 seconds is detected,whether it is the message portion or the program content portion isjudged by detecting whether or not the audio-free portions of 15 secondsexist before and after this commercial message portion. When theaudio-free portion appearing from the time t₉ and the time t₁₀ isconsidered, the audio-free portion before it has the time of 8 secondsand the audio-free portion continuing it has the time of 11 seconds.Therefore, this audio-free portion is judged as the program contentportion.

When a logical OR is calculated between the signal of the fade-outportion and the signal of the audio-free portion, the audio-free portionappearing from the time t₉ to the time t₁₀ can be judged as the programcontent portion, too.

Judgement of the CM portion can be also made by using conjointly themode judgement device 24 besides the methods described above.

The system for detecting the video signal changing portion can executethe judgement of a higher level of accuracy because it can judge notonly the switching of the scenes but also fade-out.

On the other hand, the system for detecting the video signal changingportion needs a greater data quantity and the load to the microcomputer13 becomes greater, too. To mitigate the load to the microcomputer 13,therefore, the system for detecting the fade-out portion is morepreferred. This fade-out system is particularly effective in the UnitedStates.

This embodiment can distinguish the commercial message portion from theprogram content portion by measuring the interval of the peculiar pointsof the audio signals and the video signals during recording of theprogram and can skip the CM portion by the information of the CM portionobtained by computation at the time of recording while the program isreproduced.

Because the CM information is stored in the memory circuit inside theapparatus main body, skip reproduction can be easily carried out bychecking the content of this memory circuit.

Because this embodiment detects the audio-free portion of the audiosignals-and judges the commercial message portion, it can judgerelatively easily the CM portion.

Because the embodiment judges the commercial message portion from thevideo signals, too, it can more correctly judge the CM portion.

Because the embodiment utilizes the changing portion of the video signalwhen judging the commercial message portion from the video signal, itcan judge the commercial message portion with a higher level ofaccuracy.

Because the embodiment utilizes the fade-out portion of the video signalwhen judging the commercial message portion from the video signal, itcan simplify much more the processing than when the changing portion ofthe video signal is used.

The embodiment can further improve accuracy by conducting the judgementby using the broadcasting mode in combination.

Next, another embodiment of the present invention will be explained withreference to FIG. 3.

FIG. 3 is a block diagram of a video recording/reproduction apparatusaccording to another embodiment of the present invention, wherein likereference numerals are used to identify like constituent members as inFIG. 1.

The difference of this embodiment from the first embodiment resides inthat CM judgement means not using the video signals but using the audiosignal and the broadcasting mode is employed.

First, the explanation will be given on the case where televisionbroadcasting containing the CMs is recorded by loading the magnetictape.

The radio wave of the television broadcasting is inputted to the antenna21 and is supplied to the tuner 20. The tuner 20 selects a desiredprogram. The program selected by the tuner 20 is outputted as the audiosignals by the audio signal processing circuit 10. The program is alsooutputted as the video signals by the video signal processing circuit17. When these audio signals and video signals are recorded on themagnetic tape 1, they are supplied to the switch 6 and are recorded bythe magnetic head 4 on the magnetic tape 1. The tape positioninformation read/write circuit 14 records the time codes, etc, as theposition information of the tape, with the recognition number of thetape, on the magnetic tape 1 through the magnetic head 4 simultaneouslywith the start of recording. This information is encoded and writteninto the blanking portion of the video signals, for example.

On the other hand, the signals outputted as the audio signals in theaudio signal processing circuit 10 are supplied to the audio signallevel detector 9. The audio signal level detector 9 detects themagnitude of the audio signals and supplies the magnitude of the levelto the audio signal no level detector 11. The audio signal no leveldetector 11 detects the point at which the audio signal level close tozero and supplies it detection signal to the microcomputer 13.

The microcomputer 13 stores the time of the detection signal of thistime supplied from the audio signal no level detector 11 and the tapeposition information supplied from the tape position informationread/write circuit 14, measures the time interval of the detectionsignal from the time of the next detection signal, and judges the signalwhen the interval is a constant interval. The tape position informationsupplied from the tape position information read/write circuit 22simultaneously with the output of the detection signal by the audiosignal is also stored in the 10 microcomputer 13.

When the signals are judged as the CM by the audio signals, the tapeposition information and the tape recognition numbers at the start andend of the CM are supplied to the CM information memory circuit 12. TheCM information memory circuit 12 stores the tape recognition number andthe tape position information as the CM information. The CM informationmemory circuit 12 for storing this CM information may comprise asemiconductor memory such as an EEPROM or a RAM or a magnetic tape. Inother words, the CM position information are sequentially stored in theCM information memory circuit 12 during the recording mode while theprogram is recorded.

The program so recorded is reproduced in the following way. First, thetape position information and the tape recognition number written intothe magnetic tape 1 are read out by the tape position informationread/write circuit 14. The tape position information and the taperecognition number so read out are supplied to the microcomputer 13. Themicrocomputer 13 looks up the CM position information of the tape duringreproduction, which is stored in the CM information memory circuit 12,from the tape recognition number.

The microcomputer 13 distinguishes the CM portion from the programportion from the tape position information during reproduction on thebasis of the CM position information looked up from the CM informationmemory circuit 12, and gives the fast-forward command or the fast-playcommand to the tape drive circuit 15 so as to skip the CM portion whenthe CM portion is reached. The tape drive circuit 15 drives the motor 8in accordance with this command and causes the magnetic tape 1 to travelat a high speed.

The microcomputer 13 counts the number of control pulses existing fromthe start position of the CM to its end position from the CMinformation, and counts the control pulses supplied thereto from thecontrol pulse read/write circuit 22 from the CM start position. When thenumber of the control pulses so counted reaches the number of thecontrol pulses existing in the CM portion, the microcomputer 13 gives acommand to the tape drive circuit 15 so as to stop fast-forward orfast-play and to return to standard reproduction, and the tape drivecircuit 15 drives the motor 8 and lets the magnetic tape travel at thestandard travelling speed. The subsequent CM portions are skipped in thesame way. As described above, the CM portion and the program portion aredistinguished from each other, and only the CM is skipped.

This embodiment can distinguish the commercial message portion from theprogram content portion by measuring the intervals of the peculiarpoints of the audio signals during recording of the program, and canskip the CM portion during reproduction of the program from theinformation of the CM portion obtained by calculation at the time ofrecording.

In comparison with the first embodiment shown in FIG. 1, the number ofthe factors for judging the CM becomes smaller, but the circuit scalecan be made smaller, as well. Further, the capacity of the memory forstoring the information of the peculiar points at the time of thejudgement of the CM can be reduced.

Because the CM information is stored in the memory circuit inside theapparatus main body, skip reproduction can be easily carried out bychecking the content of this memory circuit.

Because the audio-free portion of the audio signal is detected so as tojudge the commercial message portion, the CM portion can be judgedrelatively easily.

Judgement accuracy can be further improved by using the judgement by thebroadcasting mode in combination.

Next, still another embodiment of the present invention will beexplained with reference to FIG. 4.

FIG. 4 is a block diagram useful for explaining still another embodimentof the present invention, wherein like reference numerals are used toidentify like constituent members as in FIG. 1.

The difference of this embodiment shown in FIG. 4 from the firstembodiment shown in FIG. 1 resides in that the circuit 12 for storingthe CM information is not particularly disposed and the CM informationis directly written to the magnetic tape 1 to which the program isrecorded.

During recording of the program, the microcomputer 13 judges the CM fromthe audio signals and the video signals in the same way as in the firstembodiment. After recording is completed, the microcomputer 13 gives acommand to the tape drive circuit 15 to rewind the tape, so as to recordthe CM position information so judged to the magnetic tape 1. The tapedrive circuit 15 drives the motor 8 and causes the magnetic tape 1 to berewound and the CM information read/write circuit 19 records the CMinformation. To reproduce the tape, the CM position information of themagnetic tape 1 is first read out by the CM information read/writecircuit 19 and this information is stored in the microcomputer 13. Whenthe CM portion is identified from the correspondence to the tapeposition information read out by the tape position informationread/write circuit 14 from the tape 1 while the program is reproduced,this CM portion is skipped by fast-forward, etc.

The position at which the CM information is recorded will be explainedwith reference to FIG. 5.

FIG. 5 is a schematic view of the magnetic tape 1 in the longitudinaldirection in the embodiment of the invention shown in FIG. 4, and showsthe control track portion and the portion at which the video signal isrecorded.

In the example shown in FIG. 5, the portion for storing the CMinformation is provided to the winding start portion of the magnetictape 1 and all the CM information of the programs are stored in thisportion. In this example, the information of the program A and theprogram B are recorded in the leading portion (hatched portion). The CMposition information start signal is recorded in the control track atthe leading portion of the magnetic tape 1, and the CM positioninformation is so recorded in the main body recording portion of themagnetic tape 1 as to continue this CM position information startsignal. The start indexing signal is recorded in the leading controltrack of each of the programs A and B.

The recording contents of the CM position information contain theprograms A and B and the information on the CM portion interposedbetween the programs. In other words, as to the program A, the recordingcontent includes the information on the time length of the program A-1,the information of the time length of the CM continuing the program A-1,the information of the time length of the program A-2, the informationof the time length of the CM continuing the program A-2, and theinformation of the time length of the program A-3. Further, therecording content includes the information of the program B continuingthe program A, that is, the information of the time length of theprogram B-1, the information of the time length of the CM continuing theprogram B-1, the information of the time length of the program B-2 andthe information of the time length of the CM continuing the program B-2,and all of them are collectively recorded.

Reproduction is carried out in the following way. The magnetic tape 1 isonce rewound to the leading position and the CM position informationstart signal is detected. Thereafter, all the CM position information ofthe magnetic tape 1 are read out by the CM information read/writecircuit 19 by normal reproduction, and these information are stored inthe microcomputer 13. Thereafter, the CM information stored duringreproduction are allowed to correspond to the tape position informationread out by the tape position information read/write circuit 14 from themagnetic tape 1 to detect the CM portion, and when this CM portion isreached, only the CM portion is skipped by fast-forward, etc.

This embodiment can grasp the CM information of all the programs oncethe leading CM information is read out.

Because the CM information is recorded to the leading portion of thetape, all the CM information can be written again at the time ofoverwrite, too.

FIG. 6 is a schematic view of the magnetic tape 1 in the longitudinaldirection in the embodiment of the invention shown in FIG. 4, and showsthe control track portion and the portion to which the video signal isrecorded.

In the example shown in FIG. 6, the CM information is recorded at theleading portion of each of the recorded programs. In this case, theinformation of the program A and that of the program B are recorded atthe leading portions (hatched portions) of the programs A and B,respectively. The CM position information start signal is recorded atthe leading portion of each program of the control track of the magnetictape 1, and the CM position information is so recorded at the main bodyrecording portion of the magnetic tape 1 as to continue this CM positioninformation start signal. The start indexing signal is recorded in theleading control track of each of the programs A and B.

The recorded content of the CM position information described aboveincludes the information on the distinction between the program A andthe program B and the information on the CM portion interposed withinone program as shown in FIG. 6. In other words, as to the program A, therecorded content includes the information of the time length of theprogram A-1, the information of the time length of the CM continuing theprogram A-1, the information of the time length of the program A-2, theinformation of the time length of the CM continuing the program A-2 andthe information of the time length of the program A-3. As to the programB, the recorded content includes the information of the time length ofthe program B-1, the information of the time length of the CM continuingthe program B-1, the information of the time length of the program B-2and the information of the time length of the CM continuing the programB-2.

Reproduction is carried out in the following way. First, the magnetictape 1 is rewound to the leading position of each program and the CMposition information start signal is detected. Next, the CM positioninformation of the magnetic tape 1 is read out by the CM informationread/write circuit 19 by normal reproduction, and this information isstored in the microcomputer 13. Correspondence is then establishedbetween the information so stored and the tape position information readout from the magnetic tape 1 by the tape position information read/writecircuit 14 during the reproduction of the program, and only the CMportion is skipped by fast-forward, etc, when this CM portion isreached.

According to this embodiment, the tape needs be rewound only to theleading portion of each program. Therefore, the rewinding quantitybecomes smaller than in the foregoing embodiments and the operationfactor becomes higher.

In this case, the rewinding quantity to the tape after completion ofrecording becomes minimum. However, there is the possibility that the CMinformation might disappear if overwrite is effected.

In the example shown in FIG. 5, on the other hand, all the CMinformation can be rewritten at the time of overwrite because the CMinformation is recorded to the leading portion of the tape.

FIG. 7 is a schematic view of the magnetic tape 1 in the longitudinaldirection according to the embodiment of the invention shown in FIG. 4,and shows the control track portion and the portion to which the videosignal is recorded.

In the example shown in FIG. 7, the CM start signal and the CM endsignal are recorded as the CM information signals on the control tracksbefore and after each recorded program. The start indexing signal isrecorded on the leading control track of each of the programs A and B.It will be hereby assumed that the recording content of the CM positioninformation represents the start position of the CM and its endposition.

Reproduction is carried out in the following way. The CM positioninformation of the magnetic tape 1 is read out by the CM informationread/write circuit 19 while the magnetic tape 1 is normally reproduced.When the CM portion is detected from the correspondence relationshipbetween the CM position information and the tape position informationread out by the tape position information read/write circuit 14 from themagnetic tape 1 while the program is reproduced, only the CM portion isskipped by fast-forward, etc.

In this case, since the start signal of the CM and its end signal cannotbe recorded during recording of the program, the microcomputer 13 sendsthe command to the tape drive circuit 15 to drive the motor 8 and torewind the tape to the CM position on the basis of the CM positioninformation judged during recording so that the start signal and the endsignal can be recorded to the start position and the end position,respectively, after recording of the program is completed. Duringreproduction, the CM portion is fast-forwarded by reading out this CMstart signal, and the operation mode is returned to the standardreproduction at the stage where the CM end signal is read out.Accordingly, the tape need not be rewound to read out the CM informationtill the start.

According to this embodiment, the CM portion can be automaticallyskipped by normal reproduction without the necessity for rewinding themagnetic tape, and the operation factor becomes high.

According to the embodiment shown in FIG. 4, the commercial messageportion and the program content portion can be distinguished bymeasuring the intervals of the peculiar points of the audio signals andthe video signals during recording of the program. Furthermore, the CMportion can be skipped during reproduction of the program from theinformation of the CM portion that is obtained by computation duringrecording.

As already described with reference to FIGS. 1 and 3, the system usingthe CM information memory circuit can be applied only to thereproduction operation of the magnetic tape recorded by this system bythe apparatus used for recording the tape. According to the embodimentshown in FIG. 4, on the other hand, only the CM portion can be suitablyskipped by fast-play, etc, by reading the information of the leadingposition even when the magnetic tape having the CM information recordedthereto is reproduced by other apparatuses.

When the audio-free portion of the audio signal is detected as describedwith reference to FIG. 3, the commercial message portion can be judged.Therefore, the CM portion can be judged relatively easily.

The commercial message portion can be judged more accurately by judgingthe commercial message portion from the video signals, too, as describedalready with reference to FIGS. 1 and 4.

When the commercial message portion is judged from the video signal, thecommercial message portion can be judged with higher accuracy by usingthe changing portions of the video signals.

When the commercial message portion is judged from the video signal,further, the judgement process can be simplified by using the fade-outportions of the video signals in comparison with the case where thechanging portions of the video signals are used.

Accuracy of judgement can be further improved by using conjointly thejudgement by the broadcasting mode as already described with referenceto FIGS. 1, 2 5 and 4.

Next, still another embodiment of the present invention will beexplained with reference to FIG. 8.

FIG. 8 is a block diagram useful for explaining still another embodimentof the present invention, wherein like reference numerals are used toidentify like constituent members as in the embodiment shown in FIG. 3.

The difference of this embodiment from the embodiment shown in FIG. 3 isthat the CM information is written to the magnetic tape, etc, to whichthe program is recorded, without disposing the circuit for storing theCM information.

Judgement of the CM is made by the microcomputer 13 from the audiosignals at the time of recording of the program in the same way as inthe second embodiment described already. To record the positioninformation of the CM so judged after recording is completed, themicrocomputer 13 gives the command to the tape driving circuit 15 so asto rewind the magnetic tape 1, and the tape driving circuit 15 drivesthe motor 8 to rewind the magnetic tape 1, so that the CM informationread/write circuit 19 records the CM information.

When reproduction is made, the CM position information of the magnetictape 1 is read out by the CM information read/write circuit 19 and thisinformation is stored in the microcomputer 13. While the program isreproduced, this information is allowed to correspond to the tapeposition information read out from the magnetic tape 1 by the tapeposition information read/write circuit 14. When the CM portion isreached, only the CM portion is skipped by fast-forward, etc. The writeposition of the CM information is the leading position of the magnetictape or the leading portion of the program as described above, or thestart signal of the CM and its end signal are recorded to the controltracks without writing the position information.

According to this embodiment, the commercial message portion and theprogram content portion can be distinguished by measuring the intervalsof the peculiar points of the speech signals during recording of theprogram, and only the CM portion can be skipped during reproduction ofthe program from the information of the CM portion obtained bycomputation at the time of recording.

The CM position information judged in this way is recorded not to theexternal device but to the magnetic tape itself. Therefore, only the CMportion can be skipped similarly in the magnetic recording/reproductionapparatuses having this function.

Since the commercial message portion is judged by detecting theaudio-free portions of the audio signals, the CM portion can be judgedrelatively easily.

When judgement by the broadcasting mode is used in combination, accuracycan be further improved.

According to the present invention, the commercial message portion canbe distinguished even when the broadcasting mode is the same.

What is claimed is:
 1. Apparatus for recording/reproducing program material including audio and video signals on a tape recording medium, said apparatus comprising: a control pulse read/write unit which writes a pulse signal at a constant preset interval on a control track along a longitudinal direction of the tape recording medium, and reads recorded pulse signals from said control track; a recording/reproducing device coupled to receive said program material and to record and reproduce said program materials and tape position information indicative of a position on said tape recording medium, to and from oblique tracks on said tape recording medium; and a memory which stores therein recorded position information concerning a position of a commercial message portion along said longitudinal direction of said recording medium, and from which recorded position information can be read out and a control unit which, in reproduction of said program materials, controls said recording/reproducing device to start a skip of commercial message portion at a tape speed which is higher than a normal reproduction speed, based on said recorded position information read out from said memory and said tape position information reproduced from said oblique tracks on said tape recording medium, and to stop said skip in accordance with a number of control pulses read out from said control pulse read/write unit, to return to said normal reproduction speed.
 2. Apparatus for recording/reproducing program material according to claim 1 wherein said control unit controls said recording/reproducing device to skip over portions of said program material wherein time intervals between at least a pair of changing points of said audio or video signals correspond to a predetermined time interval, and occur at least two times consecutively.
 3. The apparatus according to claim 2, wherein said changing points are points at which said audio and video signals change coincidentally.
 4. The apparatus according to claim 2, wherein said changing points are points at which the audio signal level is lower than a predetermined level.
 5. The apparatus according to claim 2, wherein said changing points are points at which the audio signal level is approximately zero.
 6. The apparatus according to claim 2, wherein said changing points are points at which the video signal level changes substantially.
 7. The apparatus according to claim 2, wherein there is at least one changing point between said at least a pair of changing points.
 8. The apparatus according to claim 2, wherein said control unit controls said recording/reproducing device to reproduce portions of said program material at a standard reproduction speed wherein time intervals between changing points of said audio or video signal correspond to a predetermined time interval, and occur alone.
 9. The apparatus according to claim 1, wherein said control unit controls said recording/reproducing device to skip said commercial message portion in a fast forward or fast play mode.
 10. The apparatus according to claim 1, wherein said memory is a semiconductor memory.
 11. The apparatus according to claim 10, wherein said semiconductor memory comprises one of an EEPROM and a RAM.
 12. The apparatus according to claim 1, wherein said tape position information is a time code.
 13. The apparatus according to claim 1, wherein said tape position information is encoded and written into a vertical blanking portion of the video signal on an oblique track in said tape recording medium.
 14. A method for recording/reproducing program material including audio and video signals on a tape recording medium, said method comprising: recording said program material and tape position information indicative of a position on said tape recording medium to oblique tracks on said tape recording medium; recording control pulses at a constant preset interval on a control track along a longitudinal direction of said tape recording medium together with said program material; detecting commercial message portions during recording of said program material and storing recorded tape position information corresponding to said commercial portions, in a memory; during reproduction of recorded program material from said tape recording medium, reading position information recorded in said tape recording medium from said oblique tracks reading recorded position information of said commercial portions from said memory; and controlling said reproduction to start a skip of a commercial message portion at a tape speed which is higher than a normal reproduction speed, based on said stored position information read out from said memory and said tape position information read from said oblique tracks on said recording medium, and to stop said skip in accordance with a number of control pulses read out form said tape recording medium, to return to said normal reproduction speed.
 15. A method for recording/reproducing program material according to claim 14, wherein said step of controlling said reproduction comprises controlling said reproduction to skip over portions of said program material wherein time intervals between at least a pair of changing points of said audio or video signals correspond to a predetermined time interval, and occur at least two times consecutively.
 16. The method according to claim 15, wherein said changing points are points at which said audio and video signals change coincidentally.
 17. The method according to claim 15, wherein said changing points are points at which the audio signal level is lower than a predetermined level.
 18. The method according to claim 15, wherein said changing points are points at which an audio signal level of the program material is approximately zero.
 19. The method according to claim 15, wherein said changing points are points at which a video signal level of the program material changes substantially.
 20. The method according to claim 15, wherein there is one changing point between said at least a pair of changing points.
 21. The method according to claim 15, wherein said step of controlling reproduction includes reproducing portions of said program material at said normal reproduction speed wherein time intervals between changing points of said audio or video signal correspond to a predetermined time interval, and occur alone. 